→ Reactions taking place in an electrochemical cell are redox reactions in nature.
→ In an electrochemical cell loss of free energy appears as electrical energy.
→ The reaction in an electrochemical cell is spontaneous in nature.
→ A salt bridge maintains the electrical neutrality of the two electrolytes in their half cells.
→ The e.m.f. of an electrochemical cell is E°cathode — E°anode cathode anode
→ According to the electronic concept, the loss of electron is oxidation, and the gain of the electron is reduced.
→ The oxidation number of free elements homo atomic molecules and also of the neutral molecule is zero.
→ Electrolysis is the migration of the ions of the electrolyte towards the oppositely charged electrode when the current is passed.
→ In an electrolytic cell, the redox reaction is non-spontaneous in nature.
→ The chemical energy of the redox reaction occurring in the galvanic cell is converted into electrical energy.
→ Electrons flow from anode to cathode in the external circuit while current flow from cathode to anode.
→ 95600 c of charge represents one Faraday.
→ Oxidation: Oxidation is a process in which an atom or ion loses an electron(s).
→ Reduction: Reduction is a process in which an atom or ion gains an electron(s).
→ Oxidizing agent: (Oxidant) is a species that can readily accept one or more electrons.
→ Reducing agent: (Reductant) is a species that readily lose one or more electrons.
→ Redox Reaction: Redox reaction is a chemical reaction in which oxidation and reduction occur simultaneously.
→ Electrochemical cell: Electrochemical cell is a device in which oxidation and reduction half-reactions are carried indirectly and the loss of chemical energy during the reaction appears as electrical energy.
→ Electrolytic cell: Electrolytic cell is a device in which electrical energy is supplied from an external source to bring about a chemical reaction.
→ Anode: Anode is an electrode where the electrons are released or where oxidation takes place.
→ Cathode: A cathode is an electrode where the electrons are accepted or where reduction takes place.
→ Half cell: A half cell is a portion of an electrochemical cell in which either oxidation or reduction takes place.
→ Standard hydrogen electrode: Standard hydrogen electrode is an electrode that is used to calculate the reduction potential of another electrode. Its own reduction potential is taken as zero.
→ Standard reduction potential: Standard reduction potential of an electrode is its reduction potential as compared to that of a standard hydrogen electrode which is taken as zero.
→ Salt bridge: Salt bridge is an inverted U-shaped glass tube that contains a suitable electrolyte and connects the two-half cells in an electrochemical cell.
→ E.m.f. of a cell: E.m.f. of a cell is the difference between the reduction potential of electrodes when the cell is not sending the current.
→ Potential difference: Potential difference is the difference of potential between two electrodes when the cell is sending currents.
→ Electro-chemical series: Electrochemical series is the series obtained by arranging the electrode in order of increasing standard reduction potential values.
→ Electrolyte: Electrolyte is a substance that is capable of conducting electricity either in a molten state or when dissolved in an aqueous solution.
→ Electrolysis: Electrolysis is the process of the decomposition of an electrolyte on passing electric current.
→ Oxidation Number: The oxidation number of an element is the residual charge which its atom appears to have when all other atoms present in its combination are removed as ions.
→ Disproportionation Reaction: In this reaction, an element in one oxidation state is simultaneously oxidized and reduced.
→ Redox couple: A redox couple consists of the oxidized and reduced forms of the same substance taking part in an oxidation and reduction half-reaction.